alright, i did alittle research, it turns out that smoking out of an aluminum bowl is about as dangerous as drinking a glass of water... theres aluminum in water, and antipersperants... aluminum as small as this gets absorbed into your blood stream and accumulates in your brain, but in such tiny tiny amounts, it will do nothing to you (remember, people often grill fish and such with aluminum.. its not as bad as you all make it out to be), so if your in a pinch, go ahead and use an aluminum bowl. soda cans however, i would never use, have you ever chucked a soda or beer can in a fire, the flame turns green, i dont really wanna inhale those fumes